Nervous systems are characterized by an astounding degree of cellular diversity, yet our insights into the mechanisms of creating this diversity are limited. The molecular correlate to neuronal diversity are neuron-type specific gene expression programs. Sets of co-expressed genes that characterize an individual cell type are commonly referred to as gene batteries which are defined by their linkage to conserved, common c/s-regulatory elements. The nature of gene batteries for individual neuronal subtypes as well as their linked cis-regulatory elements are poorly described on a genome-wide level. We propose here to systematically decode cis-regulatory information on a genome-wide level and to determine the identity of a single neuron-specific gene expression program.